Some more findings:
The SR/F brake light has the rear running light and the brake actuated light. It seems the brake light is actuated by taking the white (black stripe) wire to ground...it's a ground switched circuit. The assumption here is that there are two separate circuits, one circuit being brown 12v and black ground for the running light, and the second circuit being the white (red stripe) 12v, and white (black stripe) ground for the brake light.
I also did some more testing with the GearBrake (I have the non-flashing version). It only seems like an inclinometer if its mounted level so the sensitivity is high...any declines cause the brake to light. However if mounted with an incline the sensitivity is lowered and it very obviously works as an accelerometer as long as its not at a very steep decline. This may be a non-issue by running the calibration procedure, I'll have to test.
So, I think this all means its possible to install a the GearBrake on the SR/F but it'll take some more effort:
1) Install will need a normally-open (NO) relay. The yellow and blue wires of the GearBrake would power/control the relay with the load being a tap from the white (black stripe) wire and a tap from the black wire. (A diagram would clear this up, forthcoming if I get a chance.)
2) As it's possible that either or both of circuits powering the brake light are actually from the MBB, a regular automotive relay will NOT do. The back EMF of a coil relay would likely kill the MBB...its not worth assuming the MBB has built-in protection. It'll have to be a solid state relay which completely isolates the control side from the load side of the relay.
3) Finally, my electrical knowledge gets fuzzy as to the advantages of adding diodes to further protect the MBB... I'll do more research here. I'll also share a bill of materials once it's figured out.
PaulZero if you have the time and equipment I recommend soldering your connections to prevent issues down the road. Posi-Taps would be a great alternative otherwise, they provide a more secure connection than bullets.
As to the LED indicators from Zero, they're in the 2020 accessory catalog but without a description of how they work. I doubt they'll sweep, most OEM LED indicators work as standard flashing units. For the price they're probably asking, it may be worth looking as some of the indicators from Motogadget or Rizoma. Either way, as Crissa said, it'll require the dealer updating your bike for LED indicators...the issue is whether the update would work for aftermarket indicators or just the Zero indicators.